Our Passive Solar Design
There are many ways to design a custom, passive solar, sustainable, green home. This is a good thing because, it turns out, every customer has their own, unique set of wants, needs and goals. For some people, a custom passive solar home that fits their budget is the most important thing. Others will have extended families under their new roof, or physical limitations or serious hobbies that require custom spaces. Still others have a life long dream to owner-build or owner contract their custom solar home. As custom passive solar home designers, our greatest joy is using our creativity to respond directly to the needs of each of our wonderful clients, then watching their excitement and pleasure as the design of their very own, custom solar home begins to take shape.
We began designing super energy efficient passive solar homes in the 1970's when (we like to say) it was popular the first time. As the idea caught on around the country and more families began living in passive solar homes, those of us in the industry began to hear stories about the passive solar design strategies that worked and those that didn't. Our founder, Jon Davis, always 20 years ahead of his time, studied the science and listened to the experiences and made it his goal to take passive solar design to the next level. Sunlight Homes began to innovate and over the following decades, Jon developed Sunlight Homes' approach and philosophy for designing homes that excelled in comfort, energy efficiency, sustainability, livability and style. Our second generation family business uses his guiding principals to this day.
Rethinking Passive Solar Design
Traditional passive solar home plans and designs, with their many south windows, bermed, windowless north sides, trombe walls, clerestories and tons of thermal mass were energy efficient and sustainable, but they were also very expensive and tended to overheat and fade furniture with their enormous south-facing windows. You could identify a passive solar home design a mile away because they had their own architectural look; one that doesn't fit the aesthetics of everyone. There was room for improvement.
The conventional approach to passive solar home plans is illustrated in the diagram with the full circles. First, the heat loss is calculated for the size of the structure and the climate. Then the amount of south facing glass is determined for the desired solar gain. The thermal mass is then sized in proportion to the solar gain.
In rethinking this approach, we realized that the most crucial element in a passive solar home is a super insulated exterior shell. Increasing insulation and decreasing infiltration significantly cuts heat loss, which changes the relationship between solar gain to floor area and reduces the amount of south glass and thermal mass needed. As illustrated with the half-circles, increasing insulation reduces the need for as much south facing glass and therefore as much thermal mass. Importantly, this also opens up design options, so that passive solar homes can be designed in conventional architectural styles that don't look "solar."
Structural Insulated Panels (SIPs)
In the late 1970s we found the super insulated building system we had been seeking when we discovered polyurethane structural insulated panels (SIPs). We built our first SIP home at that time and have been building with SIPs ever since.
Today we design passive solar homes in most architectural styles, ranch, Southwestern, Craftsman, prairie, contemporary and many more. We place windows where they are most useful and attractive and on all 4 sides of the home! Every primary, daytime room has abundant day lighting, with light coming in from at least 2 sides. Super insulation and low infiltration means that temperatures are more stable and comfortable year round... naturally. Our new generation homes are beautiful, functional, healthy and super energy efficient, using renewable energy and new, smart materials for the exterior shell that insulate better in less space. They are also more cost effective, more comfortable and much more aesthetically pleasing that their 1970s predecessors.
Developing our new approach to passive solar home design allowed us to also incorporate Christopher Alexander's Pattern Language design philosophy and patterns into our design process, which we consider as important as our commitment to sustainable, green architecture. Read more about this further on in this section.
Thoughtfully designed, energy efficient, solar homes are still more expensive to build initially, but they are much higher quality structures, and this is pays back monthly with lower utility bills and greatly enhanced year-round comfort. These are the very things that make our homes a better long-term investment, and a more attractive option for future buyers. Furthermore, living in an ecologically-friendly home helps keep our environment clean and reduces the use of fossil fuels, making a much lighter carbon footprint. We like that.